Generation and Characterization of Mid-Infrared Supercontinuum in Bulk YAG Pumped by Femtosecond 1937 nm Pulses from a Regenerative Amplifier

Abstract

We have demonstrated the generation of supercontinuum (SC) pulses in bulk, using femtosecond pulses directly derived from a Tm:YAP regenerative amplifier. The SC spans from 380 nm–4 μ m. Such an SC combined with the applied 1937-nm pump pulse can be used in a mid-infrared optical parametric amplifier (MIR-OPA). A full characterization of the phase and stability of the SC provides important insight into the performance of such MIR-OPA systems. Using cross-correlation frequency-resolved optical gating (XFROG), we characterized the properties of the MIR section of the SC that can be used as a seed pulse in an MIR-OPA system. The pulse-to-pulse instability rooted in the intrinsic properties of the self-phase modulation process was observed in the retrieved trace and spectrum of the SC. In addition, the effect of the pump pulse quality was studied on the obtainable SC pulses.